Q1. A dairy farmer is interested in breeding cows that are both resistant to mad cow disease (as indicated by a blood test) and brown. Each of these traits is controlled by a single locus. Resistance (R) is dominant to non-resistance (r) and brown (B) is dominant to white (b). He has noticed that brown cows are often resistant and suspects that the two traits are actually controlled by a single gene with pleiotropic effects (as in that they are completely linked).

Q2. A 40-year-old male who was seropositive for HIV experienced abdominal pain, fatigue, and low-grade fever (38°C) for two weeks. A chest X-ray examination revealed lung infiltrates. Gram and acid-fast stains were negative. A viral culture revealed the cause of his symptoms: a large, enveloped polyhedral virus with double-stranded DNA. What is the disease? Which virus caused it? Why was the viral culture completed after the Gram and acid-fast stain results were obtained?